Self-regulating thermal target

Abstract

A thermal target including a substrate and a positive temperature coefficient heater. The positive temperature coefficient heater includes at least one pattern of conductive ink printed on the substrate. The positive temperature coefficient heater is configured to provide at least one thermal signature. The positive temperature coefficient heater includes at least one Thermal Coefficient of Resistance (TCR) profile which increases at a set temperature to maintain the at least one thermal signature.

What is claimed is: 
     
         1 . A thermal target, comprising:
 a substrate; and   a positive temperature coefficient heater comprising at least one pattern of conductive ink printed on the substrate, the positive temperature coefficient heater being configured to provide at least one thermal signature, the positive temperature coefficient heater comprising at least one Thermal Coefficient of Resistance (TCR) profile which increases at a set temperature to maintain the at least one thermal signature.   
     
     
         2 . The thermal target of  claim 1 , wherein the positive temperature coefficient heater is configured to accurately simulate the at least one thermal signature of a given subject without experiencing thermal runaway. 
     
     
         3 . The thermal target of  claim 1 , wherein the positive temperature coefficient heater is configured to couple with and receive an amount of current from a power source, wherein the positive temperature coefficient heater is configured to self-regulate the amount of current. 
     
     
         4 . The thermal target of  claim 1 , wherein the at least one TCR profile increases by a factor of two at the set temperature. 
     
     
         5 . The thermal target of  claim 1 , wherein the at least one TCR profile is exponential. 
     
     
         6 . The thermal target of  claim 1 , wherein the positive temperature coefficient heater comprises two or more differing TCR profiles, wherein each TCR profile increases at a respective set temperature to maintain a respective thermal signature. 
     
     
         7 . The thermal target of  claim 1 , wherein the positive temperature coefficient heater comprises a first pattern of conductive ink and a second pattern of conductive ink which differs from the first pattern of conductive ink. 
     
     
         8 . A method for producing a thermal target, comprising:
 providing a substrate and a positive temperature coefficient heater comprising conductive ink and at least one Thermal Coefficient of Resistance (TCR) profile, the positive temperature coefficient heater being configured to provide at least one thermal signature;   selecting a set temperature; and   printing at least one pattern of the conductive ink on the substrate,   wherein the at least one TCR profile is configured to increase at the set temperature to maintain the at least one thermal signature.   
     
     
         9 . The method of  claim 8 , further comprising adjusting an ink composition of the conductive ink to adjust the TCR profile. 
     
     
         10 . The method of  claim 8 , wherein the positive temperature coefficient heater is configured to accurately simulate the at least one thermal signature of a given subject without experiencing thermal runaway. 
     
     
         11 . The method of  claim 8 , wherein the positive temperature coefficient heater is configured to couple with and receive an amount of current from a power source, wherein the positive temperature coefficient heater is configured to self-regulate the amount of current. 
     
     
         12 . The method of  claim 8 , wherein the at least one TCR profile increases by a factor of two at the set temperature. 
     
     
         13 . The method of  claim 8 , wherein the at least one TCR profile is exponential. 
     
     
         14 . The method of  claim 8 , wherein the positive temperature coefficient heater comprises two or more differing TCR profiles, wherein each TCR profile increases at a respective set temperature to maintain a respective thermal signature. 
     
     
         15 . The method of  claim 8 , wherein printing the at least one pattern of the conductive ink on the substrate comprises printing a first pattern and a second pattern which differs from the first pattern.